Idle problem CURE!!!!!!!! Finally!!

I cleaned mine, and it wasnt really all that dirty, and I STILL noticed a diffreance.

Quote:

Originally Posted by Vick

Hey guys I don't have much time right now to read through all the pages, but I do have a problem and need some help. I have an 05' Cobalt SS Supercharged and i still have the warranty on it. Two weeks ago I noticed when i took it on the freeway that around 70 mph or around 3000 rpm I heard a loud vibrating noise coming from underneath the car..and yesterday it sounded like the muffler was vibrating...it has never done this before..please help! and also i just noticed my car is way more rough when its idling now...

When I feel/hear/see vibration at 70 my first thought is tire balance.

Yep, at idle when my AC is on no matter if its on 1,2,3 or 4 my rpm's jump around from 600rpm- 1300rpm... its absolutely ridiculous so I don't even use my AC anymore. I'm def gonna check the TB but I think there is something else at play for when the AC is on...

oh and thanks for lettin everyone know

Yepp i have the same idle prob wen ac is on no matter wat level...some of the vacuum lines in my hvac sys look a bit cracked tho so im gonna try n replace those n clean the tb hopefully somin good comes of it

ok, i have been one of the thousands of victims of the horendous idle problem with my 07' cobalt ss supercharged. I do have many mods including the stage 2 upgrade along with the k+n typhoon cold air intake system and exhaust and many more. I noticed shortly after installing the stage 2 kit that my cars idle was bouncing at idle and the problem got worse and worse to the point whereas i was stalling in traffic. I was forced to basically ride my clutch like nobodys business and it was just plain annoying. Pulling up to a red light and people looking at me thinking i was a young 16 year old wanting to show my ride up cause my rpm was consistentally bouncing from 400-1400. My fuel mileage has progressively gotten worse and it had started to become a safety issue considering i was almost t-boned as i rolled through a downhill stop sign trying to beat traffic but my car stalled again!!!

Anyhow, i am aware that there are many other balt owners out there who are experiencing the same problem as myself and i have seen what others were trying to do to fix this god aweful problem with no prevail. I have been working with the head gm tech in my city here for a while now to see if we could finally put this issue to rest. After months and months of monkeying around and ruling almost everything out except for a possible computer error in the car that wasnt tripping any codes which would be unlikely i thought to remove my throttle body to have a look. Just for the record all of you cobalt owners this is soo simply a blind monkey can remove the throttle body. Simply remove your intake and the throttle body is attached with 4-10mm bolts and 1-vacuum line and 1-electrical connector. Once removed i noticed that i had a bit of gunk in the body(not a significant amount and keep in mind my car have only 5k miles on it) but i figured i would give it a good cleaning with a $5 spray can of throttle body cleaner and then clean right around the valve(keep in mind when you open the valve be very gentle when cleaning to avoid any unwanted strain or possible damage). Once this minor operation was finished i reinstalled everything back to normal and fired it up and hot damn!!!! Back to normal baby! Everything is running 100%. No more funky butterfly idle problems and my gas mileage is back to normal.

I cant believe i didnt figure this out long ago but s**t happens i guess. Anyhow, i know many of you are going to be wanting to jump all over this and fix your own problem but read this before you do. I dont like just fixing problems and saying "great its done" i want to know what caused this considering the car is so new with so few miles on it??? Im not 100% sure but i would assume it has alot to do with the filter being mounted so close to the ground and possibly some oil from the k+n filter and mabye some other debris happen to make its way up which would be strang but no impossible. My only possible solution to this rather than doing this cleaning every 5k miles would be for all of us to install oil catch tanks to allow some of this crud to remove itself from the intake and then every once in a while remove the vacuum line on your intake while the car is running and give the hole in the intake a quick spray of the throttle body cleaner.

Ohh and for you wanting to know why this problem was doing what it was doing is simply this - when there is any type of crud or oily compound around your intake valve and the valve may possibly stick a bit the vehicle recognized this and sees that it is sticking so it rushes to correct and overcorrects causing the valve to be opened to much and drops quickly causing the fluctuation from anywhere from a couple hundred rpm to 1500 rpm or so. I hope to god that this helps hundreds if not thousands of other owners out there who have been experiencing this problem because it drives us crazy!!! And i was near ready to go buy a gallon of gas and a match if a solution didnt come along right soon. Anyhow, please post replies once this is tried and let me know. I am very very curious as to how many people this is going to help.

ok so your saying my cone filter is dirty and needs clean sorry i never learned to read explain again?

ok so your saying my cone filter is dirty and needs clean sorry i never learned to read explain again?

no wat hes sayin is to clean ure throttle body bc alot of times with the cai being routed soo low it picks up water...oil from the filter and oilly air in general, and some sludge can get back up as a cause form this so hes sayin to clean outt the tb and I would recommend a catch can to prevent somin lke this from happenin again...i bought my greddy from ebay it hooked right up and been wrking wonders!

no wat hes sayin is to clean ure throttle body bc alot of times with the cai being routed soo low it picks up water...oil from the filter and oilly air in general, and some sludge can get back up as a cause form this so hes sayin to clean outt the tb and I would recommend a catch can to prevent somin lke this from happenin again...i bought my greddy from ebay it hooked right up and been wrking wonders!

Ok understood oil from the filter is getting to the tb along with what else gets thru the filter.
How much was ur catch can?
Thanx for putting it in retard form. I understand now.

I bought my Ion Redline with about 90k miles on it. Was having a little surge and got worse over a few more thousand miles. Took the TB off and it was pretty gunky around the blades. Obviously never cleaned. I cleaned it and the surge went away completely.

I bought my Ion Redline with about 90k mile son it. Was having a little surge and got worse over a few more thousand miles. Took the TB off and it was pretty gunky around the blades. Obviously never cleaned. I cleaned it and the surge went away completely.

Ok understood oil from the filter is getting to the tb along with what else gets thru the filter.
How much was ur catch can?
Thanx for putting it in retard form. I understand now.

np ne time ik it is a little difficult to understand. I bought a greddy catch can new gen it ran me bout 90 on ebay but its cause it makes my bay look a little dressed up...u can get a cheaper aluminum one fer 40 or plastic fer 20...if u want cheap i wud go with the aluminum 40 ther awesome n still cheap

np ne time ik it is a little difficult to understand. I bought a greddy catch can new gen it ran me bout 90 on ebay but its cause it makes my bay look a little dressed up...u can get a cheaper aluminum one fer 40 or plastic fer 20...if u want cheap i wud go with the aluminum 40 ther awesome n still cheap

I've had this problem a couple of months after I bought my car, and It got so damn bad I was about to sell or trade it in. But about 20 min ago I cleaned my tb and it runs like a brand new ******* car, i'm so happy =]

Im having problems with my 2.2. Only when the AC is on though, the rpm's jump between 4-800 and shutters when shifting gears (A/T). I'm hoping the shifting is related *fingers crossed*. Im going to give this a try Friday, I'll post results as well.

ok i have a 06 ss sc n i just had the tb cleaned n it fixed the problem of my bouncein idle but now i have a high idle for instance when i am driving and then i come to a light the rpm gauge stays at like 1500 n after a good amount of time it will drop to normal any suggestions

I have to look at the balt tb but I know on my camaro the idler valve is connected to the tb/ throttle plate and if its like that on the balt when you cleaned you tb you may have either knocked the idler or over cleaned it and thats what is causing your revs to over compinsate on idle

I think i might have to try this. My car has been ideling rough when i start it up lately. After it runs awhile its ok but right when i start it up its bad. Great info i think im gonna do that this week.

how do i fix the problem n is it doing any damage by driving it around

no no damage is being done....if its what I think it is you just trew off the idler which is a spring related item the regulates your engines rpm based on airflow it could just be drawing in more are and reving higher...also check all your vacuum lines attached to the tb if one is cracked or not on all the way alot more air will be drawn in causing a high reving idle!!!

A few notes. When my MAF was dirty it really messed up my car to the point where it felt like it was knocking! Cleaned it off and ran perfectly. It is a very typical problem if you have a K&N filter. The oil on the K&N filters (ecspecially since you apply yourself) gets on the MAF sensor.

Also... The 05-06 models do need the reflash. There is a bulletin out for it that reads "Engine reprogramming - fluctuating RPM's". The 07 models have that level flash already as built. Heard this from the third GM service place I called. The first two were azz stupid and I had to hang up because they couldn't even look the bulletin up after I gave them the number... LoL